In building construction and reconstruction, utilities and other facilities such as piping, conduit, duct, light fixtures, and communications wiring, for example, are commonly supported from building structural elements such as beams, purlins, trusses, roofs, or concrete floors above a suspended ceiling. These facilities are usually secured in place by a wide variety of hangers or suspenders, ranging from clips or clamps to wire or chain. Examples of such construction fasteners and hangers are sold under the well-known CADDY® trademark by Erico International Corporation of Solon, Ohio U.S.A. Wires have been widely used for suspension of such items including the suspended ceiling itself.
Wire or cable kits have also been employed for suspension purposes and examples may be seen in U.S. Pat. Nos. 2,819,923 and 6,003,210. Both use a wire sling with a loop at one end and an adjustable cleat forming a loop around the object suspended. The problem with both is that the bottom or free end of the length of wire or cable has to be passed over the structural object, through the loop on the upper end, and then pulled tight. If the cleat is on the wire, it may have to be removed and reattached, particularly if there is a clearance problem above or through the structural object. The thread-through loop system of the prior patents also limits the possibility of securing the length of wire to the suspended or stayed object first, and then to the structure for final adjustment. Some suspended objects require lateral stability, particularly in seismic zones, so that the length of wire is not always plumb. Also, the wire may be used to form a horizontal catenary between two structural members and from which additional wire slings may be used to support or stay other objects.
The noted prior patents illustrate cleats for forming adjustable loops where the cleat is designed to accommodate a single or limited size of wire. Also, both use a low angle wedge surface to grip the wire against a linear surface. In the earlier patent, the wedge surface is the threads of the set screw. If adjustment or repositioning is required, it is not always easy to release the grip on the wire, or a special tool may be required. It would be desirable if the cleat would accommodate a range of wire sizes, and for each provide a tighter, more secure grip, and yet one which is easily released.
It would also be desirable to have a cleat which optionally can be locked in its cable or wire gripping condition so that seismic anomalies or vibrations cannot release the wire or cable, even momentarily.
It would further be desirable for the suspension system to include cleats or terminations which would enable the system to be attached directly or indirectly to various devices or objects such as light fixtures so that they could be hung or supported without encircling the object with a loop.